Aspects of the bioavailability of topical corticosteroid formulations
- Authors: Magnus, Ashley Denis
- Date: 1979
- Subjects: Adrenocortical hormones , Dermatopharmacology , Dermatologic agents , Transdermal medication
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3724 , http://hdl.handle.net/10962/d1001458
- Description: Two possible variables of the McKenzie/Stoughton blanching assay, namely amount applied to the test site and occlusion time have been investigated. Subsequently, two topical steroid preparations, Synalar cream (0,025% fluocinolone acetonide) and Betnovate cream (0,1% betamethasone 17- valerate) were extemporaneously diluted with five and six placebo bases respectively. Taking cognizance of the two possible variables, these diluted preparations were assessed in vivo using a modified version of the McKenzie/Stoughton blanching assay for blanching activity over a 14 month period. It was found that the base E45, which is slightly alkali, had the greatest effect on both preparations. In the case of betamethasone 17-valerate this base caused the conversion to the less active isomer, betamethasone 21-valerate whereas at the end of the 14 month test period it was found that the Synalar/E45 dilution contained no fluocinolone acetonide. Quantitative analysis of all the diluted preparations by high performance liquid chromatography using a reverse-phase system was performed. The data obtained from the systematic studies of the effects of varying concentrations and occlusion times were presented at the Eleventh National Congress of the South African Pharmacological Society
- Full Text:
- Authors: Magnus, Ashley Denis
- Date: 1979
- Subjects: Adrenocortical hormones , Dermatopharmacology , Dermatologic agents , Transdermal medication
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3724 , http://hdl.handle.net/10962/d1001458
- Description: Two possible variables of the McKenzie/Stoughton blanching assay, namely amount applied to the test site and occlusion time have been investigated. Subsequently, two topical steroid preparations, Synalar cream (0,025% fluocinolone acetonide) and Betnovate cream (0,1% betamethasone 17- valerate) were extemporaneously diluted with five and six placebo bases respectively. Taking cognizance of the two possible variables, these diluted preparations were assessed in vivo using a modified version of the McKenzie/Stoughton blanching assay for blanching activity over a 14 month period. It was found that the base E45, which is slightly alkali, had the greatest effect on both preparations. In the case of betamethasone 17-valerate this base caused the conversion to the less active isomer, betamethasone 21-valerate whereas at the end of the 14 month test period it was found that the Synalar/E45 dilution contained no fluocinolone acetonide. Quantitative analysis of all the diluted preparations by high performance liquid chromatography using a reverse-phase system was performed. The data obtained from the systematic studies of the effects of varying concentrations and occlusion times were presented at the Eleventh National Congress of the South African Pharmacological Society
- Full Text:
The in vivo and quantitative assessment of topical corticosteroid formulations
- Authors: Coleman, Gerald Leslie
- Date: 1978 , 2013-10-14
- Subjects: Dermatopharmacology , Dermatologic agents , Skin absorption , Adrenocortical hormones -- Therapeutic use , Transdermal medication -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3857 , http://hdl.handle.net/10962/d1013337
- Full Text:
- Authors: Coleman, Gerald Leslie
- Date: 1978 , 2013-10-14
- Subjects: Dermatopharmacology , Dermatologic agents , Skin absorption , Adrenocortical hormones -- Therapeutic use , Transdermal medication -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3857 , http://hdl.handle.net/10962/d1013337
- Full Text:
The study of the metabolism of phenylbutazone (4-butyl-1,2 -diphenylpyrazolidine - 3,5 - dione) in rats
- Authors: Alexander, Dorothy Mary
- Date: 1978 , 2013-10-18
- Subjects: Drugs -- Metabolism , Phenylbutazone
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3832 , http://hdl.handle.net/10962/d1007468 , Drugs -- Metabolism , Phenylbutazone
- Description: In this study the metabolism of the anti-arthritic drug, phenylbutazone, was investigated in female Wistar rats, and the results compared with those of other workers in this field. Two interrelated projects were undertaken. The first covered the pattern of excretion, isolation and characterisation of the metabolites and decomposition products of phenylbutazone in rats dosed post-orally with the drug. It was found that the major route of excretion was via the urine and over 50% of the administered dose was excreted in the first 24 hours by this route. A small percentage of the dose was excreted in the faeces. The following compounds were identified using chromatographic and autoradiographic techniques: p-Hydroxy derivative of phenylbutazone γ-Hydroxy derivative of phenylbutazone in both its molecular forms (ring lactone and straight chain hydroxyl) 4-Hydroxy derivative of phenylbutazone p-γ-Dihydroxy derivative of phenylbutazone p-4-Dihydroxy derivative of phenylbutazone Hydrolysable conjugates (possibly glucuronides) Water soluble non-hydrolysable conjugates. The second project dealt with the quantitation of the water insoluble compounds isolated in the initial work. Using a unique technique, combining inverse isotope dilution assay and spectrophotometric analysis, it was found that the major metabolite was the γ-hydroxy derivative of phenylbutazone, present in both its molecular forms. Oxyphenbutazone was a minor metabolite and the p-γ-dihydroxy derivative of phenylbutazone was present only in very low concentration. These results did not conform with those of previous workers in this field who reported the γ-hydroxy derivative of phenylbutazone, in one molecular form only, as the major metabolite and the dihydroxy derivative as the second metabolite with a higher concentration in the urine than oxyphenbutazone. This disparity could be due to the fact that these workers took no account of the presence of the two molecular forms of the γ-hydroxy derivative of phenylbutazone with their different polarities and different Rf values. The present study showed that the straight chain hydroxyl isomer was probably mistakenly identified as the p-γ-dihydroxy derivative of phenylbutazone. This theory is supported by the fact that the percentage dose recovered by the previous workers of the γ-hydroxy and p-γ-dihydroxy derivatives together equalled the percentage dose recovered in this study of the two molecular forms of the γ-hydroxy derivative. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Alexander, Dorothy Mary
- Date: 1978 , 2013-10-18
- Subjects: Drugs -- Metabolism , Phenylbutazone
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3832 , http://hdl.handle.net/10962/d1007468 , Drugs -- Metabolism , Phenylbutazone
- Description: In this study the metabolism of the anti-arthritic drug, phenylbutazone, was investigated in female Wistar rats, and the results compared with those of other workers in this field. Two interrelated projects were undertaken. The first covered the pattern of excretion, isolation and characterisation of the metabolites and decomposition products of phenylbutazone in rats dosed post-orally with the drug. It was found that the major route of excretion was via the urine and over 50% of the administered dose was excreted in the first 24 hours by this route. A small percentage of the dose was excreted in the faeces. The following compounds were identified using chromatographic and autoradiographic techniques: p-Hydroxy derivative of phenylbutazone γ-Hydroxy derivative of phenylbutazone in both its molecular forms (ring lactone and straight chain hydroxyl) 4-Hydroxy derivative of phenylbutazone p-γ-Dihydroxy derivative of phenylbutazone p-4-Dihydroxy derivative of phenylbutazone Hydrolysable conjugates (possibly glucuronides) Water soluble non-hydrolysable conjugates. The second project dealt with the quantitation of the water insoluble compounds isolated in the initial work. Using a unique technique, combining inverse isotope dilution assay and spectrophotometric analysis, it was found that the major metabolite was the γ-hydroxy derivative of phenylbutazone, present in both its molecular forms. Oxyphenbutazone was a minor metabolite and the p-γ-dihydroxy derivative of phenylbutazone was present only in very low concentration. These results did not conform with those of previous workers in this field who reported the γ-hydroxy derivative of phenylbutazone, in one molecular form only, as the major metabolite and the dihydroxy derivative as the second metabolite with a higher concentration in the urine than oxyphenbutazone. This disparity could be due to the fact that these workers took no account of the presence of the two molecular forms of the γ-hydroxy derivative of phenylbutazone with their different polarities and different Rf values. The present study showed that the straight chain hydroxyl isomer was probably mistakenly identified as the p-γ-dihydroxy derivative of phenylbutazone. This theory is supported by the fact that the percentage dose recovered by the previous workers of the γ-hydroxy and p-γ-dihydroxy derivatives together equalled the percentage dose recovered in this study of the two molecular forms of the γ-hydroxy derivative. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
A study of the rabbit eye test system to determine the activity of acidic non-steroidal anti-inflammatory agents
- Authors: Wiseman, Ian Charles
- Date: 1977
- Subjects: Nonsteroidal anti-inflammatory agents , Anti-inflammatory agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3855 , http://hdl.handle.net/10962/d1013276
- Description: From introduction : "Inflammation per se, has been defined sufficiently to permit a rational approach to the search for drugs that modify this process, but satisfactory animal models for most rheumatoid diseases are not available". (Swingle 1974) In the search for new meaningful procedures for the detection and evaluation of anti-inflammatory drugs, the rabbit eye as a test system was studied.
- Full Text:
- Authors: Wiseman, Ian Charles
- Date: 1977
- Subjects: Nonsteroidal anti-inflammatory agents , Anti-inflammatory agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3855 , http://hdl.handle.net/10962/d1013276
- Description: From introduction : "Inflammation per se, has been defined sufficiently to permit a rational approach to the search for drugs that modify this process, but satisfactory animal models for most rheumatoid diseases are not available". (Swingle 1974) In the search for new meaningful procedures for the detection and evaluation of anti-inflammatory drugs, the rabbit eye as a test system was studied.
- Full Text:
Interactions between steroidal anti-inflammatory agents and collagen
- Authors: Kanfer, Isadore
- Date: 1975
- Subjects: Anti-inflammatory agents Collagen
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3849 , http://hdl.handle.net/10962/d1012620
- Description: Much research has been done on the formation of fibrils from solutions of soluble collagen in vitro in order to gain some knowledge of the mechanisms which may occur in vivo. The in vitro formation of fibres from solutions of collagen has been shown to be extremely sensitive to the nature of the solution environment and the presence of added chemical compounds, and thus constitutes an interesting system for the study of collagen-small molecule inter actions. The present study is concerned with the effects of various corticosteroid drugs, used medicinally as anti-inflammatory agents, on collagen in solution. As these corticosteroids are administered to reduce inflammation in conditions such as rheumatoid arthritis and a host of other pathological conditions in which collagen is implicated, this work has been undertaken in order to establish and charac teri ze any binding mechanisms which may be involved. Furthermore, the corticosteroid drugs available commercially in pure form as the free base or as the water-soluble ester salts offer an interesting range of structural and stereochemical variants for the study of their reaction with a complex and biologically important protein molecule such as collagen. A great deal of research on drug- protein interactions (Goldstein, 1949; Meyer and Guttman, 1968a) and more specifically, steroid-protein interactions have been reported over the years (Daughaday, 1959; Sandberg et al., 1966; Villee and Engel, 1961; Westphal , 1971). Comprehensive reports, however, on steroid-collagen interactions in vitro are conspicuously absent from modern scientific literature although relatively superficial accounts have been published (Menczel and Maibach, 1972; Eik-Nes et al., 1954). Although work involving the above has appeared relating specifically to the effects of steroids on collagen biosynthesis both in vivo and in vitro there have been minimal accounts of steroid-collagen interactions tailored to characterize the binding at the molecular level. The effect of corticosteroids on the metabolism of connective tissue has also received special attention (Asboe-Hansen, 1959; Kivirikko, 1953; Nakagawa and Tsurufuji, 1972). Recently, Uitto et al. (1972) reported the effects of several anti-inflammatory corticosteroids on collagen biosynthesis in vitro, whilst Aalto and Kulonen (1972) reported the effects of several antirheumatic drugs on the synthesis of collagen and other proteins in vitro. The interactions between collagen and certain drugs has also been briefly reviewed (Chvapil, 1967). Much data also exists on the binding of a wide range of small molecules and ions with serum albumin (Steinhardt and Reynolds, 1969; Scatchard, 1949; Klotz, 1950). Serum albumin, being specialized for a very general transport function and apparently designed for the purpose of combining with a large range of small molecules, has a proportion of possible reactive sites 'buried' within the molecule itself because of its folded conformation. In addition, serum albumin shows a high degree of cooperative binding in contrast to collagen. The latter molecule, with its larger molecular size and weight is specialized for a biologically structural function and has a higher proportion of possible reactive sites which appear relatively more accessible to ligands. A study of the interactions between corticosteroids and collagen thus provides the opportunity to investigate a protein which is very different from the much studied serum albumin. Because of the limited information available regarding the interaction of steroid drugs and collagen at the molecular level, studies of this nature are relevant to the understanding of the mode of action of steroid compounds which are such an important group of therapeutic substances used in modern medicine.
- Full Text:
- Authors: Kanfer, Isadore
- Date: 1975
- Subjects: Anti-inflammatory agents Collagen
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3849 , http://hdl.handle.net/10962/d1012620
- Description: Much research has been done on the formation of fibrils from solutions of soluble collagen in vitro in order to gain some knowledge of the mechanisms which may occur in vivo. The in vitro formation of fibres from solutions of collagen has been shown to be extremely sensitive to the nature of the solution environment and the presence of added chemical compounds, and thus constitutes an interesting system for the study of collagen-small molecule inter actions. The present study is concerned with the effects of various corticosteroid drugs, used medicinally as anti-inflammatory agents, on collagen in solution. As these corticosteroids are administered to reduce inflammation in conditions such as rheumatoid arthritis and a host of other pathological conditions in which collagen is implicated, this work has been undertaken in order to establish and charac teri ze any binding mechanisms which may be involved. Furthermore, the corticosteroid drugs available commercially in pure form as the free base or as the water-soluble ester salts offer an interesting range of structural and stereochemical variants for the study of their reaction with a complex and biologically important protein molecule such as collagen. A great deal of research on drug- protein interactions (Goldstein, 1949; Meyer and Guttman, 1968a) and more specifically, steroid-protein interactions have been reported over the years (Daughaday, 1959; Sandberg et al., 1966; Villee and Engel, 1961; Westphal , 1971). Comprehensive reports, however, on steroid-collagen interactions in vitro are conspicuously absent from modern scientific literature although relatively superficial accounts have been published (Menczel and Maibach, 1972; Eik-Nes et al., 1954). Although work involving the above has appeared relating specifically to the effects of steroids on collagen biosynthesis both in vivo and in vitro there have been minimal accounts of steroid-collagen interactions tailored to characterize the binding at the molecular level. The effect of corticosteroids on the metabolism of connective tissue has also received special attention (Asboe-Hansen, 1959; Kivirikko, 1953; Nakagawa and Tsurufuji, 1972). Recently, Uitto et al. (1972) reported the effects of several anti-inflammatory corticosteroids on collagen biosynthesis in vitro, whilst Aalto and Kulonen (1972) reported the effects of several antirheumatic drugs on the synthesis of collagen and other proteins in vitro. The interactions between collagen and certain drugs has also been briefly reviewed (Chvapil, 1967). Much data also exists on the binding of a wide range of small molecules and ions with serum albumin (Steinhardt and Reynolds, 1969; Scatchard, 1949; Klotz, 1950). Serum albumin, being specialized for a very general transport function and apparently designed for the purpose of combining with a large range of small molecules, has a proportion of possible reactive sites 'buried' within the molecule itself because of its folded conformation. In addition, serum albumin shows a high degree of cooperative binding in contrast to collagen. The latter molecule, with its larger molecular size and weight is specialized for a biologically structural function and has a higher proportion of possible reactive sites which appear relatively more accessible to ligands. A study of the interactions between corticosteroids and collagen thus provides the opportunity to investigate a protein which is very different from the much studied serum albumin. Because of the limited information available regarding the interaction of steroid drugs and collagen at the molecular level, studies of this nature are relevant to the understanding of the mode of action of steroid compounds which are such an important group of therapeutic substances used in modern medicine.
- Full Text:
A gas chromatographic study of oils from some Agathosma species (family Rutaceae)
- Persicaner, Peter Henry Robert
- Authors: Persicaner, Peter Henry Robert
- Date: 1972 , 2013-11-13
- Subjects: Rutaceae , Rutaceae -- Therapeutic use , Gas chromatography
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3837 , http://hdl.handle.net/10962/d1007634 , Rutaceae , Rutaceae -- Therapeutic use , Gas chromatography
- Description: From Introduction: Buchu leaf is a very widely used household medicine in South Africa, and is usually administered in the form of a brandy tincture or a vinegar, known as "buchu brandy" and "buchu vinegar" respectively. These preparations have a great reputation in curing diseases of the kidney and urinary tract, and in addition are employed as local applications to bruises, and for the relief of rheumatic pains. We owe its introduction into medicine to the Hottentot, who gave the name "buchu" or "bookoo" to any aromatic herb or shrub which they found suitable for use as a dusting powder.
- Full Text:
- Authors: Persicaner, Peter Henry Robert
- Date: 1972 , 2013-11-13
- Subjects: Rutaceae , Rutaceae -- Therapeutic use , Gas chromatography
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3837 , http://hdl.handle.net/10962/d1007634 , Rutaceae , Rutaceae -- Therapeutic use , Gas chromatography
- Description: From Introduction: Buchu leaf is a very widely used household medicine in South Africa, and is usually administered in the form of a brandy tincture or a vinegar, known as "buchu brandy" and "buchu vinegar" respectively. These preparations have a great reputation in curing diseases of the kidney and urinary tract, and in addition are employed as local applications to bruises, and for the relief of rheumatic pains. We owe its introduction into medicine to the Hottentot, who gave the name "buchu" or "bookoo" to any aromatic herb or shrub which they found suitable for use as a dusting powder.
- Full Text:
An investigation into chemical and biological assays of new compounds from aloes
- Authors: Mapp, R K
- Date: 1969
- Subjects: Medicinal plants -- Research -- South Africa , Botanical chemistry , Aloe -- Analysis , Aloe -- Research -- South Africa , Aloe , Aloin
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3850 , http://hdl.handle.net/10962/d1012830
- Description: The drug aloes has been known since earliest times and is mentioned in the Ebers papyrus of circa 1,500 B.C. Alexander the Great is reported to have sent a commission to Socotra to investigate the aloes grown there. The chemical composition of aloes is complex, and being of plant origin, subject to variation. Both the complexity of the chemical constituents and their biological variation has resulted in a very large volume of conflicting material being published on this drug export. Since aloes is used as a purgative for both human and veterinary use, it is obviously important that the dosage and consequently the active constituents, should comply to an accurate means of standardisation. To date, despite extensive world wide research into this drug such standardisation has not been achieved. Even the methods used for the assay of the principal constituent, aloin, vary considerably in their results, and to complicate matters new chemical principles have been isolated from aloes in recent years. Consequently the purpose of this work has been to investigate the main chemical assay methods currently in use, and to determine which was the most accurate, and why discrepancies occurred in the selected assay methods. furthermore the results obtained by chemical assay have been compared with those obtained by biological assay in an attempt to correlate aloin content with purgative activity. Newly isolated compounds have been investigated biologically for the first time, and the biological assays of the resinous, glycosidal and other compounds of aloes have been performed. Intro. p.1-2.
- Full Text:
- Authors: Mapp, R K
- Date: 1969
- Subjects: Medicinal plants -- Research -- South Africa , Botanical chemistry , Aloe -- Analysis , Aloe -- Research -- South Africa , Aloe , Aloin
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3850 , http://hdl.handle.net/10962/d1012830
- Description: The drug aloes has been known since earliest times and is mentioned in the Ebers papyrus of circa 1,500 B.C. Alexander the Great is reported to have sent a commission to Socotra to investigate the aloes grown there. The chemical composition of aloes is complex, and being of plant origin, subject to variation. Both the complexity of the chemical constituents and their biological variation has resulted in a very large volume of conflicting material being published on this drug export. Since aloes is used as a purgative for both human and veterinary use, it is obviously important that the dosage and consequently the active constituents, should comply to an accurate means of standardisation. To date, despite extensive world wide research into this drug such standardisation has not been achieved. Even the methods used for the assay of the principal constituent, aloin, vary considerably in their results, and to complicate matters new chemical principles have been isolated from aloes in recent years. Consequently the purpose of this work has been to investigate the main chemical assay methods currently in use, and to determine which was the most accurate, and why discrepancies occurred in the selected assay methods. furthermore the results obtained by chemical assay have been compared with those obtained by biological assay in an attempt to correlate aloin content with purgative activity. Newly isolated compounds have been investigated biologically for the first time, and the biological assays of the resinous, glycosidal and other compounds of aloes have been performed. Intro. p.1-2.
- Full Text:
An investigation of chlorbutol in ophthalmic and parenteral solutions
- Authors: Summers, Robert Stanley
- Date: 1967
- Subjects: Parenteral solutions , Solutions (Pharmacy) , Ocular pharmacology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3842 , http://hdl.handle.net/10962/d1007694 , Parenteral solutions , Solutions (Pharmacy) , Ocular pharmacology
- Description: From Introduction Chlorbutol , which is tri-chlor-tertiary-butanol, was first prepared by Willgerodt in 1886 (1). The reaction he used for its preparation is still used today, though slightly modified (2)(3)(4), and is suggested by its original name "acetone-chloroform". The substance was prepared by adding solid potassium hydroxide to a cold mixture of acetone and chloroform (5 ). Chlorbutol is a derivative of the trichlorinated derivative of methane, and its formation may best be described by the use of structural formulae.
- Full Text:
- Authors: Summers, Robert Stanley
- Date: 1967
- Subjects: Parenteral solutions , Solutions (Pharmacy) , Ocular pharmacology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3842 , http://hdl.handle.net/10962/d1007694 , Parenteral solutions , Solutions (Pharmacy) , Ocular pharmacology
- Description: From Introduction Chlorbutol , which is tri-chlor-tertiary-butanol, was first prepared by Willgerodt in 1886 (1). The reaction he used for its preparation is still used today, though slightly modified (2)(3)(4), and is suggested by its original name "acetone-chloroform". The substance was prepared by adding solid potassium hydroxide to a cold mixture of acetone and chloroform (5 ). Chlorbutol is a derivative of the trichlorinated derivative of methane, and its formation may best be described by the use of structural formulae.
- Full Text:
The phytochemistry of several South African aloe species
- Authors: McCarthy, Terence John
- Date: 1967
- Subjects: Botanical chemistry Aloe -- Research -- South Africa Aloe -- Analysis Medicinal plants -- Research -- South Africa Drugs -- Research Chromatographic analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3836 , http://hdl.handle.net/10962/d1007621
- Description: Introduction: Despite the tremendous advances made with regard to synthetic organic medicinals within the last two decades, heavy reliance is still placed on plant products. This is especially true of the anthracene derivatives used medicinally as purgatives, and which are derived principally from senna, cascara, rhubarb, frangula and aloes. While particular attention has been paid to the chemistry of the former group in recent years, aloes has been largely neglected, possibly due to the fact that the Aloe species are confined largely to areas where extensive research facilities are lacking, such as Africa , India and the West Indies. Thus research in Europe has been confined largely to the lump aloes of commerce, derived from relatively few species. In 1953 a comprehensive report by Hodge (103) appeared on "The Drug Aloes of Commerce, with Special Reference to the Cape Species". Hodge observed that South Africa abounds in species just as abundant as A.ferox, (which is the prime source of Cape aloes), and advised that a systematic chemical survey might show certain of these to be not only higher yielders of bitter aloetic juice but also sources of a superior drug product. Consequently an investigation along these lines is presented here, and it is observed that several species apart from A.ferox not only contain aloin, but also yield a large volume of aloetic juice. Only pharmacologic studies can reveal if the juice of these species is as safe as that of A.ferox, but without doubt they could be used for the extraction of crystalline aloin. Concurrently, the distribution of the Aloe resins, said by some to be purgative themselves, has been studied. The investigation has revealed that the structurally similar compound homonataloin enjoys an equally wide distribution as aloin. However, almost invariably it is confined to small species yielding little aloetic juice, apart from which nothing is known regarding its pharmacologic properties. It is interesting to note that the resin distribution in the homonataloin-containing species is very similar to that of the aloin-containing species, but differs widely from. that of the species containing neither of these principles. Apart from aloin and homonataloin, aloinoside and chrysophanol also occur in Aloe species, and together with the resins, these indicate that when all the South African Aloe species have been investigated, they may well be of chemotaxonomic value. Within the comparatively short space of the last decade some work has been performed on aspects of the metabolism of such anthracene-containing species as Rheum, Rhamnus and Rumex. These investigations have shown that the anthracene derivatives are not merely waste products, but perform definite metabolic functions. The latter portion of this work has been devoted to this relatively neglected aspect of the Aloe species.
- Full Text:
- Authors: McCarthy, Terence John
- Date: 1967
- Subjects: Botanical chemistry Aloe -- Research -- South Africa Aloe -- Analysis Medicinal plants -- Research -- South Africa Drugs -- Research Chromatographic analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3836 , http://hdl.handle.net/10962/d1007621
- Description: Introduction: Despite the tremendous advances made with regard to synthetic organic medicinals within the last two decades, heavy reliance is still placed on plant products. This is especially true of the anthracene derivatives used medicinally as purgatives, and which are derived principally from senna, cascara, rhubarb, frangula and aloes. While particular attention has been paid to the chemistry of the former group in recent years, aloes has been largely neglected, possibly due to the fact that the Aloe species are confined largely to areas where extensive research facilities are lacking, such as Africa , India and the West Indies. Thus research in Europe has been confined largely to the lump aloes of commerce, derived from relatively few species. In 1953 a comprehensive report by Hodge (103) appeared on "The Drug Aloes of Commerce, with Special Reference to the Cape Species". Hodge observed that South Africa abounds in species just as abundant as A.ferox, (which is the prime source of Cape aloes), and advised that a systematic chemical survey might show certain of these to be not only higher yielders of bitter aloetic juice but also sources of a superior drug product. Consequently an investigation along these lines is presented here, and it is observed that several species apart from A.ferox not only contain aloin, but also yield a large volume of aloetic juice. Only pharmacologic studies can reveal if the juice of these species is as safe as that of A.ferox, but without doubt they could be used for the extraction of crystalline aloin. Concurrently, the distribution of the Aloe resins, said by some to be purgative themselves, has been studied. The investigation has revealed that the structurally similar compound homonataloin enjoys an equally wide distribution as aloin. However, almost invariably it is confined to small species yielding little aloetic juice, apart from which nothing is known regarding its pharmacologic properties. It is interesting to note that the resin distribution in the homonataloin-containing species is very similar to that of the aloin-containing species, but differs widely from. that of the species containing neither of these principles. Apart from aloin and homonataloin, aloinoside and chrysophanol also occur in Aloe species, and together with the resins, these indicate that when all the South African Aloe species have been investigated, they may well be of chemotaxonomic value. Within the comparatively short space of the last decade some work has been performed on aspects of the metabolism of such anthracene-containing species as Rheum, Rhamnus and Rumex. These investigations have shown that the anthracene derivatives are not merely waste products, but perform definite metabolic functions. The latter portion of this work has been devoted to this relatively neglected aspect of the Aloe species.
- Full Text: